> After what serial number does it become the A version thanks Gee, maybe I'm missing something here, but wouldn't the easiest way to tell an A 15/3.5 from a K 15/3.5 be to look at the markings (or to look for the A setting on the aperture ring, or to look for the electrical contacts on the mount face)?
Anyhow, in case it helps, my own A 15/3.5 has a SN of 5919xxx. Fred
